Tool-feeding mechanism for lathes



(No Model.) I 2 sheetssheet 1.

/ E. s. COBB.

TOOL FEEDING MEGHANISM FOR LAT'HES. No. 322,904. Patented July 28, 1885.

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E. SJCOBB.

1300L FEBDING MBGHANISM FOR LATES.

No. 322,904. l Patented July 28, 1885.;

UNITED STATES PATENT OFFICE.

EDW'ARD S. COBB, OF TERRE HAUTE, INDIANA.

TOOLFEEDING MECHANISNI FOR LATHES.

SPECIFICATION forming part of Letters Patent No. 322,904, dated July 28, 1885.

Application tiled May 25, 1885.

To all whom it may concern:

Be it known that I, EDWARD S. COBB, a citizen of the United States, residing at Terre Haute, in thecounty of Vigo and State of Indiana, have invented a new and useful Improvement in Tool-Feeding Mechanism for J{ iathes, of which 'the following is a specificaion.

My invention relates to an improved toolfeeding mechanism for engine-lathes.

The objects of my improvement are, rst, to so combine a clutch mechanism with the tool-carriage of a lathe and with gear-wheels, and longitudinal and transverse feed-screws connected therewith, that the tool may be caused to move either longitudinally or transversely in relation to the lathe-bed, or to remain stationary, by the manipulation of a single piece mounted on the apron of the toolcarriage; second, to so arrange the clutch and the longitudinal and transverse feed mechanisms that it shall be impossible to so manipulate the said controlling piece or hand-wheel as to engage both the longitudinal and the transverse feed mechanisms at the same time;

third, to so arrange the clutch mechanism, the gears forming a part thereof, and the means forsupporting said gears and for operating the clutch, that all the strain caused by the engagement of the friction-clutch shall be selfcontained within the moving parts, and any binding or clampingof the principal revolving part in its bearing thereby avoided, all as hereinafter fully explained.

The accompanying drawings illustrate my invention.

Figure l represents a cross-section of the tool-carriage of a lathe, taken on a central line through the clutch'and feed mechanism. 4.o Fig. 2 represents an elevation of the feed mechanism and back side of the tool-carriage apron on a reduced scale.

A is the lathe-bed, B the rack-bar secured longitudinally to and along the front of the lathe- 45 bed, and G the feed-shaft mounted parallel with the rack-bar in suitable bearings on the bed.

D is the tool-carriage, adapted to slide longitudinally along the lathe-bed on suitable 5o Ways, in the usual well-known manner, and carrying the usual sliding part, d, in which the tool-post is secured.

(No model.)

The apron eof the tool-carriage is provided with a long hollow cylindrical bearing, f. Said bearing may be cast integral with the apron or formed separately and secured thereto in any suitable manner. A hollow shaft, g, is nicely fitted to the bearing f, so as to revolve freely therein. Said shaft is provided near its inner end with a collar, h, which rests against the inner end of the bearing j', and

the shaft is held in place and prevented from moving longitudinally in the bearing by a screw-collar, t, an anti-friction washer, j, being interposed between said screw-collar and the outer end of the bearing.

Upon the inner end of shaft g is mounted end of a second hollow shaft, s, which is fitted to slide longitudinally in shaft g, but is preventedfrom turning therein by a pin, t, which passes diametrically through both shafts, shaft s being slotted at u to permit its longitudinal movement.

The arrangement of clutch r and shaft s is such that while the clutch is free to revolve on the shaft it cannot move endwise thereon, being held in place by collars o and w, and moving in that direction with the shaft. A,

E is a solid shaft extending through shafts, and carrying on its inner end a pinion, x,

which intermeshes with the rack-bar B. Pinion x is so mounted on shaft s as to turn freely thereon without endwise movement, and has one side adapted to engage the clutch r, as shown. Shaft E and hollow shaft g are united so as to bear a constant fixed relation to each other by a pin, t, while hollow shaft s may be moved longitudinally in relation to both, so as, when moved in one direction, to bring the clutch r into engagement with the transverse feed mechanism, of which gear-wheel le on shaft g is a part, and when moved in the opposite direction to pass, rst, to an intermediate position where neither feed mechanism is engaged, and then, on further movement,

IOC

into engagementwith pinion x, which is a part ofthe longitudinal feed mechanism. The longitudinal movement of hollow shaft s and consequent engagement of the clutch may be accomplished from the front of the apron in several ways; but I prefer, for convenience of manufacture and ease of operation, the means shown. The projecting front ends of shafts g and E are both screw-threaded to forni screws of like pitch and direction, while shaft s is threaded to form an opposed screw-,that is, the screws on g and E being right-hand screws, the screw on s would be left-hand. A handnut, y, is fitted to engage all three of the screws, so that when the nut is turned shafts is drawn outward or pushed inward, while shafts g and E remain stationary.

For the purpose of giving motion to the feed mechanisms through clutch r, an annular screw gear-wheel, F, is fitted to the periphery of the clutch and secured thereon by. keys z z in such a manner that the clutch can slide longitudinally within the gear-wheel, but is compelled to turn therewith. The screw-gear is retained in place by the hubs of gear-wheel 7c and pinion x, and is revolved continuously by the feed-shaft C.

In a screw-cutting lathe, shaft C is usually a screw, which is connected with the tool-carriage by mechanism separate and distinct from the ordinary feed mechanism. It is obvious that said screw-shaft might engage directly with the screw gear-wheel F, and thus operate the longitudinal and transverse feed mechanism; but, for the purpose of saving the threads of shaft C from unnecessary wear, I mount a short screw-th readed sleeve, G, in suitable bearings on the tool-carriage and in engagement with wheel F. A feather, f, is secured to the inside of sleeve G and slides in a longitudinal groove in the screw-shaft C, so as to slide along and to turn therewith.

In operation, gear-wheel F and clutch r being revolved by shaft C, the operator, by turning the hand-nut i, forces shaft s inward, thus clamping clutch 4" and pinion x strongly together, causing pinion fr to revolve, and thus, through its engagement with the rack-bar B, moving the tool-carriage longitudinally.

It will be observed that the strain of the clamping action of nut y is wholly confined to theshafts g, s, and E, the clutch r, and pinion w. rlhis being the case, clutch r and pinion x cease to turn on their respective shafts, and

there being no clamping action against the ends of bearing f, and the shafts g, s, and E being compelledto revolve together by pin t, the clutch, pinion, and shafts turn as a solid mass in bearing f, while gear-wheel 7c, having no other connection with the revolving parts than its narrow bearing on shaft g, remains station ary. The operator, by turning nut y in the opposite direction, draws shaft s and the clutch out of engagement with pinion x. Said pinion is now free to turn on shaft E, and the carriage may now be moved by hand, and the gear 7o being still free, the transverse feedscrew o may also be operated by hand, the clutch r meantime revolving on shaft s. Upon turning nut ystill further, the clutch and gear 7c are clamped together and revolved together with shafts g, s, and E, which turn, as before, in bearing j'. A long and strong bearing free from clamping strain is thus given to the feed mechanism when doing work and feeding automatically, while each feed mechanism is 1ndependent and easily operated by hand.

I claim as my invention- 1. A tool-feeding mechanism for lathes, consisting of the following elements, namely: `a tool-carriage arranged to slide longitudinally on the lathe-bed and having a tool-support arranged to slide on said carriage across the lathe-bed, a screw mounted in the carriage and arranged to move said tool-support, a rack-bar secured to and along one side of the lathe-bed, a shaft mounted in bearings along one side of the lathe-bed and arranged to revolve, a hollow shaft arranged to revolve 1n a suitable bearing in the apron of the toolcarriage, a gear-wheel arranged to revolve on said shaft and to impart movement to the cross feed screw in the carriage, a central shaft passing through said hollow shaft and connected therewith so as to bear a fixed relation thereto, a pinion arranged to revolve on said central shaft and to engage the rack-bar, a second hollow shaft mounted upon said central shaft within the first hollow shaft and arranged to have a longitudinal movement in relation thereto, a doublefaced clutch mounted on said hollow shaft so as to turn thereon and to move longitudi- IOO nally therewith, and' arranged between the opposed sides of the gear connected with the cross feed screw, and the pinion engaging the rack-bar, so as to engage clutch-surfaces on either, a clamping-nut or its equivalent arranged outside of the apron of the tool-carriage and adapted to move the second hollow shaft longitudinally, and to thereby bring the clutch into engagement, an annular screw gearwheel mounted on the periphery of the clutch and secured thereto so as to revolve therewith and permit a sliding movement thereon, and a screw engaging said screw gear-wheel and actuated by the shaft on thelathe-bed, all combined and adapted to co-operate substantially as specified.

2. In a tool-feeding mechanism for lathes, the combination, with the lathe-bed, a rackbar secured thereto, a shaft arranged to revolve in bearings on the lathe-bed, and a tool-carriage arranged to slide on said bed, of a hollow shaft arranged to revolve in a bearing on the tool-carriage, a central shaft passing through said hollow shaft and connected therewith so as to bear a fixed relation thereto, a pinion arranged to revolve on said central shaft and to engage the rack-bar, a second hollow shaft mounted upon said central shaft within the iirst hollow shaft and arranged to have a longitudinal movement in relation thereto, a clutch mounted on said hollow shaft so as to IIO ISO

turn thereon and to movelongitudinally therewith, and arranged to engage a clutch-surface on the pinion which engages the rack-bar, means for moving the interior hollow shaft longitudinally, whereby the clutch is brought into engagement with the pinion, an annular screw gear-wheel mounted on the periphery of the clutch so as to turn therewith, and a screw engaging said screw gear-wheel and actuated by the shaft on the lathe-bed, all substantially as and for the purpose specified.

3. In a tool-feeding mechanism for lathes, the combination,with the lathe-bed, a shaft arranged to revolve in bearings thereon, and a tool-carriage arranged to slide longitudinally on said bed, and having a toolsupport arranged to slide across the bed, of a screw arranged to move said tool-support, a pinion on said screw, a hollow shaft arranged to revolve in a bearing on the tool-carriage, a gear-wheel arranged to revolve on said shaft and to impart movement to the cross feed screw, a second shaft fitted to the interior of the hollow shaft and connected thereto so as to revolve therewith, but capable of a-limited longitudinal movement in relation thereto, a clutch mounted on said second shaft so as to revolve thereon and to move longitudinally therewith,

and arranged to engage a clutch-surface on said gear-wheel, a clamping-nut or its equivalent arranged on said shafts and adapted to move the said second shaft longitudinally, whereby the clutch is brought into engagement, anannular screw gear-wheel mounted on the periphery of the clutch so as toturn therewith, and a screw engaging said screw gear-wheel and actuated by the shaft on thelathe-bed, all subs'tantially as and for the purpose specified.

4. The friction clutching mechanism, consisting of two hollow shafts, one arranged to slide within the other, a central shaft passing through the interior hollowshaft and connected with the exterior hollow shaft so as to bear a fixed relation thereto, clutch-wheels mounted y on each of said shafts so as to revolve thereon, and means, substantially as vshown and described, for moving the interior hollow shaft longitudinally, whereby the clutch-wheel .on said shaft is brought into engagement with either of the other clutch-wheels, all combined and arranged to co-operate substantially as specified. l

EDWARD S. COBB. Witnesses:

W. C. J oNEs, W. J. HARTMAN. 

